In most regions or geographical areas, a time-dependent usage pattern of communication is reality, wherein typically more than one mobile communication network is available within a given region or geographical area, wherein each of these mobile communication networks are serving their respective customers within that region or geographical area. In general this implies that during periods of low demand (e. g. during the night) each of the mobile communication networks is overdimensioned because normally the mobile communication networks are designed for peak time (usually day time) demand. This results in unnecessary energy consumption by the mobile communication networks during those low demand periods. The low demand periods are hereinafter also called off-peak times.
In the context of the Third Generation Partnership Project (3GPP), attempts have already been made regarding solutions for energy saving of components of mobile communication networks. Such energy savings are especially realized by switching off radio equipment components on the networks side. As a consequence, a user equipment currently being served by the radio equipment subject to being switched off will have to find an alternative, either in the same RAT (Radio Access Technology), or in another RAT (Radio Access Technology). Examples of such specifications include 3GPP TR 24.826 V0.5.0, 3GPP TR 25.927 V10.0.0, and 3GPP TR 32.826 V10.0.0.
However these solutions only provide energy saving mechanisms within one mobile communication network, i.e. within the network of one operator of a mobile communication network. Hence each individual operator's network has to be capable of scaling its capacity, and power consumption, between peak and off-peak demand. In areas of high peak-time demand, i.e. where the network has a high capacity, a high scaling factor between the peak time and the off-peak time—where there might be very few users on the network—is required, which might not be technically feasible. Moreover, this problem is aggravated if the said operator's network supports two different RATs, e.g. GERAN and UTRAN in 3GPP-based networks. In this case, at least one GERAN cell and one UTRAN cell has to be kept available in off-peak times in order to support both the GSM and UMTS terminals, even in cases where a single cell of any RAT would be sufficient to sustain the total number of terminals during off-peak time. Thus, in many scenarios, the efficiency of the energy saving mechanisms suffers from the “single-operator” limitation.